Retrospective study. The aim of this study is to evaluate the predictive ability of pre-operative Scoliosis Research Society-22 revised questionnaire (SRS-22r) domains for achieving Minimum clinically important difference (MCID) at 2 years after adolescent idiopathic scoliosis (AIS) surgery. Understanding which AIS will achieve clinically meaningful postoperative benefit remains challenging, particularly when counseling families about expected changes in health-related quality of life. MCID thresholds for SRS-22r domains have been described, but it is unclear how baseline profiles can be leveraged to anticipate meaningful improvement at 2 years after surgery. A retrospective analysis of AIS patients undergoing posterior spinal fusion was performed. Pre-operative, 1-year, and 2-year SRS-22r domain scores (Function, Pain, Self-Image, Mental Health), VAS pain, and ODI were collected. MCID was defined as a ≥ 1-point improvement from baseline to 2 years. Univariate and multivariable logistic regression models were constructed, and model performance was assessed using ROC–AUC and calibration curves. ROC-based threshold optimization using Youden’s J statistic, and fivefold cross-validation was used to derive clinically interpretable pre-operative cut-points. In total, 189 patients were analyzed for the study. All SRS-22r domains improved significantly at 2 years, with the greatest absolute gain in Self-Image 64.9

ABSTRACT High inpatient opioid exposure is associated with increased risk of persistent opioid use, yet early identification of high-risk patients during hospitalization remains limited. We developed and evaluated machine learning models to predict extreme opioid exposure using electronic health record data from MIMIC-IV. This retrospective cohort-based prediction modeling study included 223,452 unique first hospital admissions. The outcome was extreme opioid exposure, defined as the top decile of morphine milligram equivalents (MME) per day among opioid-exposed admissions (corresponding to ≥225 MME/day in the development cohort), representing 2.65% of all admissions. Structured early-admission features included demographics, admission characteristics, laboratory utilization and abnormality summaries, and 24-hour procedural indicators. Discharge-note data were incorporated using ClinicalBERT embeddings and bigram features. Models were trained using an 80/10/10 split, with temporal validation performed on the most recent 10% of admissions. External validation was conducted using the MIMIC-III and eICU Collaborative Research Database cohorts. Performance was assessed using ROC-AUC and PR-AUC with 95% confidence intervals. Among structured-only models, XGBoost achieved the best internal test performance (ROC-AUC 0.932 [0.924-0.940]; PR-AUC 0.223 [0.193-0.262]). A combined structured and notes model improved precision-recall performance (ROC-AUC 0.932 [0.920-0.943]; PR-AUC 0.276 [0.229-0.331]). Temporal validation showed similar discrimination (ROC-AUC 0.929; PR-AUC 0.223). In external validation, performance decreased substantially. In MIMIC-III, the model achieved ROC-AUC 0.669 [0.659-0.680] and PR-AUC 0.018 [0.017-0.019], while in eICU performance was further attenuated (ROC-AUC 0.567 [0.556-0.576]; PR-AUC 0.018 [0.017-0.019]). Predicted probabilities were poorly calibrated in both external datasets, with limited correspondence between predicted and observed risk. These findings demonstrate that while EHR-based machine learning models can achieve strong internal discrimination, their performance and calibration may degrade substantially across independent healthcare systems -- underscoring the need for dataset-specific validation and recalibration prior to clinical application. AUTHOR SUMMARY Opioid medications are commonly used in hospitals to treat pain, but some patients receive very high doses, which may increase their risk of long-term opioid use and dependence. Identifying these high-risk patients early during hospitalization could help doctors make safer prescribing decisions and improve pain management. In this study, we analyzed electronic health record data from over 220,000 hospital admissions to develop machine learning models that estimate which patients are likely to receive high levels of opioids. We focused on information available within the first 24 hours of admission, including patient characteristics, laboratory testing patterns, and procedures. We also examined whether information from clinical notes could improve predictions. We found that the models performed well within the original dataset, and that combining structured data with clinical notes improved performance. The patterns identified by the models -- such as links to surgical procedures and more intensive care -- were in line with expectations. However, when the models were tested in different hospital datasets, performance declined, and predicted risks no longer matched what actually happened to patients. These findings highlight an important challenge in applying machine learning in healthcare: models that perform well in one setting may not work reliably in others. While routinely collected hospital data may help identify patients at risk early, predictive models must be carefully tested and adapted before they can be safely used in new clinical environments.

Retrospective study. This study uses receiver operating characteristic (ROC)-based minimal clinically important difference (MCID) analysis to quantify which radiographic changes best predict meaningful functional and pain improvements following posterior spinal fusion for Scheuermann’s kyphosis (SK). SK is a rigid spinal deformity resulting in significant back pain and functional impairment, commonly affecting adolescents and young adults. Surgical correction aims to restore sagittal balance, but the relationship between radiographic correction and patient-reported outcomes is not well-defined. A retrospective cohort of 40 patients aged 15–35 with SK who underwent posterior spinal fusion and osteotomies was analyzed. Pre- and postoperative radiographs were reviewed for thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence–lumbar lordosis mismatch (PI–LL), and T1 pelvic angle (TPA). Functional and pain outcomes were measured via Oswestry Disability Index (ODI) and Visual Analog Scale (VAS) at final follow-up (minimum 24 months for all patients), with MCID thresholds used to dichotomize outcomes; multivariable regression identified the strongest radiographic predictors. Surgical correction yielded significant improvements in alignment (mean TK reduced from 85.6° to 46.3°, PI–LL mismatch from 27.5 to 10.1; p < 0.001). VAS scores improved by 1.39 points (p = 0.010) and ODI by 6.6 (p = 0.011, Wilcoxon). Clinically meaningful pain relief was achieved in the majority, with about half exceeding MCID for function. ROC analysis revealed that final PI–LL mismatch was the most predictive of functional improvement (AUC up to 0.81 for correction magnitude), with thresholds favoring near-neutral or slightly negative alignment. For pain relief, a greater degree of TK correction was the best predictor (AUC 0.60). LL and TPA showed limited predictive power for outcomes. Multivariable models demonstrated high apparent discrimination (AUC up to 0.97) but tended to overestimate mid-range probabilities due to small sample size. Achieving near-neutral PI–LL mismatch and maximally reducing thoracic kyphosis are key for optimizing functional and pain outcomes in SK surgery. The study supports targeting individualized radiographic corrections over universal alignment thresholds for best clinical improvement. IV.

Posterior decompression for cervical spondylotic myelopathy (CSM) halts neurological decline, but postoperative rehabilitation remains poorly standardized. Existing literature focuses on isolated modalities rather than an integrated, time-based strategy. We performed a narrative evidence synthesis, rather than a formal systematic review or meta-analysis, to identify optimal rehabilitation timing, progression, and adjunctive modalities after posterior cervical surgery and to propose a structured clinical pathway intended to guide, rather than replace, clinical decision-making. Four databases were searched (PubMed, Embase and MEDLINE [via Ovid], Web of Science; 1990–2025). Studies on postoperative rehabilitation following posterior cervical decompression (laminoplasty or laminectomy ± fusion) were included if they reported pain, function, neurologic recovery, quality of life, or performance outcomes in ≥ 10 patients. Data extraction included intervention type, timing, outcome measures, and functional gains. Narrative synthesis compared early (≤ 4 weeks) vs delayed (> 4 weeks) rehab initiation. Twenty-nine studies met criteria. Consistent and early rehabilitation was generally associated with superior outcomes across heterogeneous studies. Among timing-specific studies, 10/13 (77

STUDY DESIGN:Retrospective study. OBJECTIVE:This study explores the associations between thoracic inlet angle (TIA) and key cervical alignment measures, including T1 slope (T1S), cervical lordosis (CL), and cervical sagittal vertical alignment (cSVA), to provide insight into alignment relationships and postoperative recovery following multilevel posterior cervical fusion. Patients were stratified using an exploratory preoperative TIA-CL difference (PreopΔ) to examine descriptive recovery patterns in the context of demographic factors such as body mass index (BMI), age, and smoking status. SUMMARY OF BACKGROUND DATA:TIA is a morphologic, anatomically fixed parameter that has been shown to correlate with cervical sagittal alignment. However, its association with postoperative recovery patterns remains incompletely defined, and its role is distinct from validated mismatch parameters such as T1S-CL. METHODS:A total of 157 patients undergoing multilevel posterior cervical fusion were analyzed for associations between TIA and T1S, CL, and cSVA at preoperative, 1-month, 1-year, and 2-year time points. Patients were stratified into 3 exploratory subgroups based on PreopΔ (TIA-CL) values. RESULTS:Significant associations were observed between TIA and T1S ( r =0.76, P <0.001) and between TIA and CL ( r =0.63, P <0.001). Subgroup analyses demonstrated descriptive differences in radiographic and functional outcomes; however, demographic factors such as BMI, age, and smoking status differed between groups and were strongly associated with outcome variability. Among patients in the lowest PreopΔ subgroup, smokers demonstrated higher 2-year ODI scores ( P <0.001). CONCLUSIONS:TIA is anatomically associated with cervical sagittal alignment and provides a morphologic reference for understanding postoperative alignment patterns. Observed subgroup differences represent descriptive, hypothesis-generating associations rather than predictive or causal relationships.

Study Design. Systematic review, PROSPERO ID: (CRD42023112392). Objective. We aim to provide physicians with an evidence-based stepwise approach to distinguishing the primary cause of plane pelvic obliquity (PO) to guide treatment. Summary of Background Data. PO is a frequent clinical finding in both spinal deformity (SD) and leg length discrepancy (LLD) but distinguishing between these etiologies remains challenging due to overlapping clinical and radiographic features and potential multifactorial origins. Misdiagnosis may delay care and worsen patient outcomes. Materials and Methods. PubMed, Embase, Scopus, and Web of Science were searched from inception to July 2025 for English-language studies evaluating coronal PO in the context of LLD and/or SD that explicitly compared or differentiated limb-origin from spine-origin obliquity using radiographic, advanced imaging, or validated clinical assessments and reported diagnostic accuracy, discriminative features, or management impact. Two reviewers independently screened studies, extracted data, and performed ROBINS-I risk assessment and Newcastle-Ottawa Scale quality assessment. Owing to marked heterogeneity in populations, measurement protocols, and thresholds, findings were synthesized qualitatively with stratification by age group where possible. Results. Of 436 records, 24 cohort studies met the inclusion criteria. Standing anteroposterior (AP) radiographs reliably quantified both LLD and PO, while advanced imaging provided high reproducibility for subtle or ambiguous cases. Radiographic block or shoe lift correction tests distinguished limb-origin and spine-origin PO through immediate postural correction. Key discriminators included a lumbar curve or PO resolving with block/lift correction suggesting LLD, versus persistent deformity despite correction suggesting spinal etiology. Difficulty remains in diagnosing and treating mixed etiology patients. Conclusion. Accurate differentiation of spinal versus limb-driven PO begins with a structured diagnostic approach. AP radiographs, followed by functional block tests, and advanced imaging, may increase diagnostic confidence and decrease unnecessary interventions. Particularly in patients with both LLD and coronal plane SD, prospective studies are required to standardize measurement protocols and improve long-term outcomes. Level of Evidence. Level IV.

STUDY DESIGN:Systematic review, PROSPERO ID: (CRD42023112392). OBJECTIVE:We aim to provide physicians with an evidence-based stepwise approach to distinguishing the primary cause of plane pelvic obliquity (PO) to guide treatment. SUMMARY OF BACKGROUND DATA:PO is a frequent clinical finding in both spinal deformity (SD) and leg length discrepancy (LLD) but distinguishing between these etiologies remains challenging due to overlapping clinical and radiographic features and potential multifactorial origins. Misdiagnosis may delay care and worsen patient outcomes. MATERIALS AND METHODS:PubMed, Embase, Scopus, and Web of Science were searched from inception to July 2025 for English-language studies evaluating coronal PO in the context of LLD and/or SD that explicitly compared or differentiated limb-origin from spine-origin obliquity using radiographic, advanced imaging, or validated clinical assessments and reported diagnostic accuracy, discriminative features, or management impact. Two reviewers independently screened studies, extracted data, and performed ROBINS-I risk assessment and Newcastle-Ottawa Scale quality assessment. Owing to marked heterogeneity in populations, measurement protocols, and thresholds, findings were synthesized qualitatively with stratification by age group where possible. RESULTS:Of 436 records, 24 cohort studies met the inclusion criteria. Standing anteroposterior (AP) radiographs reliably quantified both LLD and PO, while advanced imaging provided high reproducibility for subtle or ambiguous cases. Radiographic block or shoe lift correction tests distinguished limb-origin and spine-origin PO through immediate postural correction. Key discriminators included a lumbar curve or PO resolving with block/lift correction suggesting LLD, versus persistent deformity despite correction suggesting spinal etiology. Difficulty remains in diagnosing and treating mixed etiology patients. CONCLUSION:Accurate differentiation of spinal versus limb-driven PO begins with a structured diagnostic approach. AP radiographs, followed by functional block tests, and advanced imaging, may increase diagnostic confidence and decrease unnecessary interventions. Particularly in patients with both LLD and coronal plane SD, prospective studies are required to standardize measurement protocols and improve long-term outcomes. LEVEL OF EVIDENCE:Level IV.

This abstract reflects content previously published in the following source: Singh D, Truumees E, Duncan A, Laviolette M, Kohli V, Stokes J, Geck M. P481: Identifying preoperative predictors of clinically meaningful outcomes in chronic low back pain: a detailed MCID-based analysis. Global Spine J. 2025 May 21;15(2 Suppl):413S–792S.https://pmc.ncbi.nlm.nih.gov/articles/PMC12099171/.

STUDY DESIGN:Retrospective cohort study. OBJECTIVES:To understand the associations between vertebral artery injury (VAI) and adverse events in patients sustaining blunt cervical spine trauma. SUMMARY OF BACKGROUND DATA:To date, the impact of VAI on adverse events, and by extension, clinical outcomes has been extracted from small patient cohorts and have not allowed definitive conclusions. METHODS:Adult patients with cervical vertebral, ligamentous, or neurological trauma in the National Trauma Data Bank from 2016 to 2017 were included in the study. Demographic information (age, sex, and race), injury-specific information (mechanism, severity), patient health information, and presence of a VAI were collected as explanatory variables. Response variables included development of adverse events [DVT/PE, myocardial infarction (MI), stroke, hemorrhage, or neurological deficit] length of stay (LOS) and unplanned ICU admission or surgical procedure. Multivariable regression was used to calculate the risk-adjusted effect of vertebral artery injury on the presence of adverse and unplanned events as well as its relationship with LOS. RESULTS:Totally, 128,908 patients with cervical trauma were reviewed, of which 5300 had VAI. Of the patients with VAI, 187 (3.5%) patients had a MI, 156 (2.9%) had a PE/DVT, 196 (3.7%) had a stroke, 1392 (26.3%) had neurological injury, and 443 (8.4%) had an unplanned operative procedure or ICU admission. After risk-adjustment, VAI was associated with a >2-fold increased risk of increased LOS and ICU LOS ( P <0.001), as well as greater than a 2-fold increased risk of MI, PE/DVT, stroke, and neurological injury ( P <0.001). CONCLUSIONS:Our study documented a higher rate of concomitant VAI in blunt cervical trauma than previously reported. VAI is a hallmark of a more severe or higher energy mechanism of injury and is associated with increased adverse events and LOS in the hospital/ICU. In addition, these data suggest that, in older patients, concomitant VAI is associated with adverse outcomes independent of mechanism of injury. LEVEL OF EVIDENCE:Step II-diagnostic study.

Health literacy (HL) is a multidimensional construct influencing patients' ability to access, understand, and use health information. In certain clinical contexts, higher HL has been linked to improved treatment decision making and outcomes. Its role in patients with spinal complaints remains underexplored. We aim to systematically review existing literature examining the association between HL and treatment selection and outcomes in adult patients presenting with spinal complaints. Comprehensive literature search of PubMed, Embase, CINAHL, Web of Science, and Google Scholar (January 2005-June 2025) was performed using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. Inclusion required use of validated HL assessment and reporting of treatment selection or outcome data. Risk of bias assessed with the Joanna Briggs Institute checklist. Certainty of evidence evaluated using GRADE. Three cross-sectional studies met inclusion criteria. Higher HL was associated with reduced surgical acceptance and increased second opinion seeking. Adequate HL was linked to greater medication adherence and follow-up in one study. No significant association was found between HL and postoperative drug-related problems. Educational attainment correlated with HL but did not fully account for differences. Racial and ethnic data were not reported. Higher HL may influence treatment selection in spinal care by reducing surgical acceptance and promoting active decision making. Evidence for HL's impact on treatment adherence and outcomes is limited and mixed. The small number of studies, cross-sectional designs, and lack of diverse samples limit generalizability. Future longitudinal and interventional studies should clarify HL's role in spinal treatment pathways and inform the development of HL-sensitive interventions.

Study design/setting: Retrospective cohort analysis. Objective: To determine what factors are associated with high-risk daily morphine milligram equivalent (MME) totals in patients undergoing spinal decompression. Background: Daily dosages of >= 100 MME/d are associated with an almost 9-fold increased risk of overdose. Current general recommendations endorse the lowest effective dose and <= 50 MME/d. Materials and methods: Retrospective analysis was conducted on 260 patients who underwent spinal decompressive surgery. Average MME/d was calculated as the sum of qualifying inpatient MMEs administered divided by the sum of inpatient length of stay. Independent variables across demographic, clinical, and surgical domains were subject to comparative and logistic regression analysis. Results: Overall MME per day was 54.19 +/- 39.37, with a range of 1.67-218.34 MME/d. Sixty-six patients were determined to have "high-risk MME." These patients were significantly younger (58.8 +/- 13.1 vs 70.53 +/- 11.5; P < 0.001) and reported higher preoperative pain visual analog scale (VAS; 4.8 +/- 3 vs 2.8 +/- 3.3; P = 0.0021) than the patients at low risk. In addition, high-risk patients had significantly higher body mass indexes (BMIs; P < 0.05) and received ketamine as part of anesthesia ( P < 0.05). Patients who consumed high-risk dosages of MMEs in the perioperative period were more likely to have been on opioids before surgery and to report higher pain scores at 4-6 week follow-ups ( P < 0.05). The final logistics regression model identified independent risk factors to be younger age, higher BMIs and preoperative VAS, and prior use of opioids and intraoperative ketamine. Conclusions: Patients with high MME per day who underwent spinal decompression were significantly younger with higher BMIs and preoperative VAS with an increased incidence of preoperative opioid use and intraoperative ketamine. A closer look at interaction models revealed that a combination of high preoperative pain and intraoperative ketamine usage were at a significantly increased risk of higher MME consumption. Preoperative opioid risk education and mitigation strategies should be considered in patients with high MME risk, especially in younger patients already utilizing opioids before surgery.

Objective: This study compared the impact of minimally invasive surgery (MIS) and open spinal deformity corrections on the paraspinal musculature and soft tissues in adolescent idiopathic scoliosis (AIS) patients by analyzing early postoperative serum tissue injury markers and later radiographic evidence of muscle atrophy within the paraspinal musculature until 6-month and 2-year postoperative follow-ups. Methods: Prospective data were collected at a single tertiary care center from January 1, 2015 to November 30, 2020. Demographic, clinical, laboratory, and radiographic data, including postoperative magnetic resonance imaging, were collected at various intervals. Results: Forty-four patients met the inclusion criteria. The mean estimated blood loss and mean operative time differed significantly between the groups. On postoperative day 1, the Open group had significantly higher serum aldolase concentrations (18.2 +/- 7.6 mU/mL vs. 12.9 +/- 4.2 mU/mL) and creatine kinase (CK) values (3,003.1 +/- 60.1 IU/L vs. 1,649.4 +/- 40.6 IU/L) than the MIS patients. In the Open group, serum aldolase and CK levels remained higher through postoperative day 4. The normalized difference in the loss of paraspinal muscle mass was higher in the Open group than in the MIS group. Patient-reported outcomes improved in both groups, but there were no significant between-group differences. Both groups reported similar complication rates. Conclusion: In patients with AIS, MIS was associated with lower tissue injury markers and muscle atrophy than open surgical correction in the early postoperative period. While this difference may be associated with decreased blood loss and shorter hospital stays seen in MIS, it did not result in a significant difference in clinical outcomes versus open surgery.

This abstract reflects content previously published in the following source:Singh D, Truumees E, Moroz E, Duncan A, Geck M, Stokes J, Laviolette M, Kohli V. P156: Impact of T1 slope-cervical lordosis discrepancy on sagittal vertical axis and patient reported outcomes following posterior cervical fusion: a multi-center retrospective analysis. Global Spine J. 2025 May 21;15(2 Suppl):413S-792S. https://pmc.ncbi.nlm.nih.gov/articles/PMC12099171/

Retrospective analysis. This study sought to report the long-term outcomes of patients that underwent minimally invasive surgery (MIS) correction for Adolescent Idiopathic Scoliosis (AIS) in terms of radiographic, clinical, and patient-reported outcomes. Furthermore, we examined the learning curve of MIS technique over the course of 13 years. Both MIS and open techniques are used to surgically address AIS. MIS techniques are purported to preserve the midline spinal musculature and to decrease estimated blood loss (EBL) and hospital length of stay (LOS). Data were collected at a single tertiary care center of all consecutive AIS patients undergoing deformity surgery from January 2008 to October 2021. Demographic, clinical, and radiographic data were collected at various intervals. Descriptive and inferential analyses were conducted. 70 AIS patients were included in the study. Mean patient age was 16.2 years of which 95.7

This narrative review seeks to enhance our comprehension of how Minimal Clinically Important Difference (MCID) and Patient Acceptable Symptom State (PASS) values in established Patient Reported Outcome Measures (PROMs) for spine surgery correspond with patient preoperative expectations and postoperative satisfaction. Through our literature search, we found that both MCID and PASS serve as dependable indicators of patient expectations. However, MCID may be more susceptible to a floor effect. This implies that PASS may offer a more accurate reflection of how patients anticipate surgery to address their symptoms. Nevertheless, it is crucial to recognize that achieving MCID or PASS may not be an absolute prerequisite for patients to be satisfied with their treatment.

This abstract contains content that is significantly similar to the authors' previously published abstract in the Global Spine Journal ePosters. For access to the original publication, please visit the following DOI: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11086047/.

This abstract contains content that is significantly similar to the authors' previously published abstract in the Global Spine Journal ePosters. For access to the original publication, please visit the following DOI: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11086047/pdf/10.1177_21925682241239483.pdf.

BACKGROUND CONTEXT The relationship between T1 Slope and Cervical Lordosis (CL), much like the relationship between Pelvic Incidence (PI) and Lumbar Lordosis (LL), serve as indicators of not only spinal alignment, but also outcomes related to overall disability and pain. PURPOSE To investigate the effect of T1-CL on outcomes in patients undergoing multi-level cervical fusions, and to establish a normative value of T1-CL in this cohort. STUDY DESIGN/SETTING Multi-center retrospective analysis. PATIENT SAMPLE A total of 356 patients undergoing long posterior cervical fusions. OUTCOME MEASURES T1 slope, C2-C7 cervical lordosis, C2-C7 Sagittal Vertical Axis, patient reported outcomes. METHODS Demographics, radiographic measurements (T1 slope, C2-C7 CL, C2-C7 Sagittal Vertical Axis (SVA)), patient reported outcomes, complication and revision data. RESULTS A total of 356 patients from seven different centers were included in analysis. Mean age was 63 ±12 years, mean BMI 28.7±6.4. There was a strong correlation between T1 and CL (r=0.79), and positive correlation between T1-CL and SVA (r=0.76), ODI (r=0.62) and VAS (r=0.65). Patients were divided into 3 different groups based on the distribution of T1-CL data: Group 1, T1-CL <34°; Group 2, 34°≥T1-CL≤56.4°; Group 3 T1-CL >56.4°. Group 1 had better alignment (20.6 mm), VAS (3.2) and ODI (32.6) as compared to Groups 2 (SVA 52.9, VAS 4.8, ODI 45.2) and 3 (SVA 70.4, VAS 5.4, ODI 47.4) at 2 years follow-up. SVA of Group 1 improved significantly more than those in Groups 2 and 3. There was no difference in complication and revision rates between three groups. Analysis revealed that T1-CL demonstrated a constant value of 21.7° (r2=0.68). A subgroup analysis with T1-CLvalue between 21.7° and 34°, vs others revealed a significant improvement in alignment, disability and pian. CONCLUSIONS T1 slope and CL and are strongly correlated, and when a parameter of T1-CL is created, that value, in turn, is positively correlated with SVA, as well as pain and disability scores. Patients with T1–CL values (between 21.7° and 34°) were significantly better aligned and reported less pain and lower disability scores. A range of T1-CL between 21.7° to 34° may be necessary to maintain horizontal gaze. FDA Device/Drug Status This abstract does not discuss or include any applicable devices or drugs.

This abstract has been previously published as part of the American Academy of Orthopaedic Surgeons 2024 Annual Meeting proceedings. For full access to the abstract, please visit the following URL: https://index.mirasmart.com/AAOS2024/PDFfiles/AAOS2024-002903.PDF.

Background Context Standing multiview X-rays and MRIs/CTs are standards of care in preoperative planning for patients undergoing cervical fusions. However, the positioning of the patient varies between the two different types of imaging. When positioned for an MRI/CT, the patient is supine, and the neck bolstered or supported. Whereas for standing X-Rays, the patient adopts their native posture and head alignment. This creates a discrepancy in values of radiographic measurements when comparing film to scan. Purpose The purpose of this study was to quantify and compare the imaging measurements between the two imaging modalities and determine if the degree of cervical flexibility had an impact clinical outcome. Study Design/Setting Retrospective study. Patient Sample A total of 227 adult spine patients. Outcome Measures Clinical and patient reported outcomes. Methods This study assessed 227 adult patients who underwent a three or more level posterior cervical fusion. Data collected included demographics, smoker status, radiographic measurements (T1 Slope, C2-C7 Lordosis, C2-C7 Sagittal Vertical Axis) from both XR films and MRI/CT scans, surgical and complication, as well as patient reported outcome measures for pain (Visual Analog Scale, VAS) and disability (Oswestry Disability Index, ODI). For each measurement technique, three cohorts were created based on distribution of the Δ between XR and MRI/CT values. Finally, the effect of demographic variables on measurement Δ was assessed. Results Overall, the cohort (n=227) was 53.7% female, with a mean age of 63 ± 13 years and BMI of 28.93 ± 6.6, 44% were never smokers. The most frequently treated (42.3%) spinal levels were C3-C7. Median Δ T1 Slope was 9°, with a range of -1° to 45°. T1 Slope cohorts: Group I with a Δ of <4°; Group II ≥4° to <15°; Group III ≥15°. Significant differences between Group I and Group III existed in VAS (4.19 and 6.59, respectively) and ODI (35.4 and 45.9, respectively). For Δ C2-C7 Lordosis, the median Δ value was 4°, with a range of -11° to 44°; Group I had a Δ lordosis of <2°; Group II ≥2 to < 7°; Group III ≥7°. Significant differences between Group I and III existed in VAS (4.6 and 6.3, respectively) and ODI (36.7 and 45.5, respectively). Median Δ C2-C7 SVA was 14.37mm, with a range of 37.6mm to 110.2mm. SVA Group I had a Δ of <7.87mm; Group II ≥7.87mm to <27.82mm; Group III ≥27.82mm. There were significant differences between Group I and Group III in VAS (4.8 and 6.4, respectively) and ODI (34 and 45.6, respectively). Revision and complication rates positively correlated with increased Δ measurement. ANOVA analysis of the effect of age, sex, gender, BMI and smoking status on each measurement technique demonstrated age having a significant effect on Δ C2-C7 SVA (p<0.05). Conclusions Larger Δ or cervical flexibility between XR and MRI/CT measurements are positively correlated with higher complication and revision rates. Patients with greater incidences of cervical flexibility reported significantly higher pain and disability scores compared to those with lower measurement Δ. Age was found to significantly impact Δ SVA measurement. FDA Device/Drug Status This abstract does not discuss or include any applicable devices or drugs.